<?php

/* ------------------------------------------------------------------------ */
/* EasyPeasyICS
/* ------------------------------------------------------------------------ */
/* Manuel Reinhard, manu@sprain.ch
/* Twitter: @sprain
/* Web: www.sprain.ch
/*
/* Built with inspiration by
/" http://stackoverflow.com/questions/1463480/how-can-i-use-php-to-dynamically-publish-an-ical-file-to-be-read-by-google-calend/1464355#1464355
/* ------------------------------------------------------------------------ */

/* History:
/* 2010/12/17 - Manuel Reinhard - when it all started
/* ------------------------------------------------------------------------ */

class EasyPeasyICS {

    protected $calendarName;
    protected $events = [];


    /**
     * Constructor
     * @param string $calendarName
     */
    public function __construct($calendarName = "") {
        $this->calendarName = $calendarName;
    }//function


    /**
     * Add event to calendar
     * @param string $calendarName
     */
    public function addEvent($start, $end, $summary = "", $description = "", $url = "") {
        $this->events[] = [
            "start"       => $start,
            "end"         => $end,
            "summary"     => $summary,
            "description" => $description,
            "url"         => $url
        ];
    }//function


    public function render($output = true) {

        //start Variable
        $ics = "";

        //Add header
        $ics .= "BEGIN:VCALENDAR
METHOD:PUBLISH
VERSION:2.0
X-WR-CALNAME:" . $this->calendarName . "
PRODID:-//hacksw/handcal//NONSGML v1.0//EN";

        //Add events
        foreach ($this->events as $event) {
            $ics .= "
BEGIN:VEVENT
UID:" . md5(uniqid(mt_rand(), true)) . "@EasyPeasyICS.php
DTSTAMP:" . gmdate('Ymd') . 'T' . gmdate('His') . "Z
DTSTART:" . gmdate('Ymd', $event["start"]) . "T" . gmdate('His', $event["start"]) . "Z
DTEND:" . gmdate('Ymd', $event["end"]) . "T" . gmdate('His', $event["end"]) . "Z
SUMMARY:" . str_replace("\n", "\\n", $event['summary']) . "
DESCRIPTION:" . str_replace("\n", "\\n", $event['description']) . "
URL;VALUE=URI:" . $event['url'] . "
END:VEVENT";
        }//foreach


        //Footer
        $ics .= "
END:VCALENDAR";


        if ($output) {
            //Output
            header('Content-type: text/calendar; charset=utf-8');
            header('Content-Disposition: inline; filename=' . $this->calendarName . '.ics');
            echo $ics;
        } else {
            return $ics;
        }

    }//function

}//class